Installation

• Since v1.0.0 (alpha/beta), OpenKruise requires Kubernetes version >= 1.16.

• Since v1.5.0(alpha/beta), OpenKruise no longer supports dockershim. If you still use Docker Engine to run containers in Kubernetes, you can Migrate Docker Engine nodes from dockershim to cri-dockerd.

• Since v1.6.0 (alpha/beta), OpenKruise requires Kubernetes version >= 1.18. However it's still possible to use OpenKruise with Kubernetes versions 1.16 and 1.17 as long as KruiseDaemon is not enabled(install/upgrade kruise charts with featureGates="KruiseDaemon=false")

• Since v1.6.0 (alpha/beta), KruiseDaemon will no longer support v1alpha2 CRI runtimes. However, it is still possible to use OpenKruise on Kubernetes clusters with nodes that only support v1alpha2 CRI, as long as KruiseDaemon is not enabled (install/upgrade Kruise charts with featureGates="KruiseDaemon=false").

Install with helm

Kruise can be simply installed by helm v3.5+, which is a simple command-line tool and you can get it from here.

# Firstly add openkruise charts repository if you haven't do this.
$ helm repo add openkruise https://openkruise.github.io/charts/

# [Optional]
$ helm repo update

# Install the latest version.
$ helm install kruise openkruise/kruise --version 1.7.2

Note: Changelog.

Upgrade with helm

# Firstly add openkruise charts repository if you haven't do this.
$ helm repo add openkruise https://openkruise.github.io/charts/

# [Optional]
$ helm repo update

# Upgrade to the latest version.
$ helm upgrade kruise openkruise/kruise --version 1.7.2 [--force]

Note that:

1. Before upgrade, you must firstly read the Change Log to make sure that you have understand the breaking changes in the new version.
2. If you want to drop the chart parameters you configured for the old release or set some new parameters, it is recommended to add --reset-values flag in helm upgrade command. Otherwise you should use --reuse-values flag to reuse the last release's values.
3. If you are upgrading Kruise from 0.x to 1.x, you must add --force for upgrade command. Otherwise it is an optional flag.

Optional: download charts manually

If you have problem with connecting to https://openkruise.github.io/charts/ in production, you might need to download the chart from here manually and install or upgrade with it.

$ helm install/upgrade kruise /PATH/TO/CHART

Options

Note that installing this chart directly means it will use the default template values for Kruise.

You may have to set your specific configurations if it is deployed into a production cluster, or you want to configure feature-gates.

Optional: chart parameters

The following table lists the configurable parameters of the chart and their default values.

setup parameters

Parameter	Description	Default
featureGates	Feature gates for Kruise, empty string means all enabled	""
installation.namespace	Namespace for kruise installation	kruise-system
installation.createNamespace	Whether to create the installation.namespace	true
installation.roleListGroups	ApiGroups which kruise is permit to list, default set to be all	*
crds.managed	Kruise will not install CRDs with chart if this is false	true
imagePullSecrets	The list of image pull secrets for kruise image	[]

manager parameters

Parameter	Description	Default
manager.log.level	Log level that kruise-manager printed	4
manager.replicas	Replicas of kruise-controller-manager deployment	2
manager.image.repository	Repository for kruise-manager image	openkruise/kruise-manager
manager.image.tag	Tag for kruise-manager image	v1.7.2
manager.resources.limits.cpu	CPU resource limit of kruise-manager container	200m
manager.resources.limits.memory	Memory resource limit of kruise-manager container	512Mi
manager.resources.requests.cpu	CPU resource request of kruise-manager container	100m
manager.resources.requests.memory	Memory resource request of kruise-manager container	256Mi
manager.metrics.port	Port of metrics served	8080
manager.webhook.port	Port of webhook served	9443
manager.pprofAddr	Address of pprof served	localhost:8090
manager.nodeAffinity	Node affinity policy for kruise-manager pod	{}
manager.nodeSelector	Node labels for kruise-manager pod	{}
manager.tolerations	Tolerations for kruise-manager pod	[]
manager.resyncPeriod	Resync period of informer kruise-manager, defaults no resync	0
manager.hostNetwork	Whether kruise-manager pod should run with hostnetwork	false
manager.loggingFormat	Logging format, valid formats includes (plain text), json

daemon parameters

Parameter	Description	Default
daemon.extraEnvs	Extra environment variables that will be pass onto pods	[]
daemon.log.level	Log level that kruise-daemon printed	4
daemon.port	Port of metrics and healthz that kruise-daemon served	10221
daemon.pprofAddr	Address of pprof served	localhost:10222
daemon.resources.limits.cpu	CPU resource limit of kruise-daemon container	50m
daemon.resources.limits.memory	Memory resource limit of kruise-daemon container	128Mi
daemon.resources.requests.cpu	CPU resource request of kruise-daemon container	0
daemon.resources.requests.memory	Memory resource request of kruise-daemon container	0
daemon.affinity	Affinity policy for kruise-daemon pod	{}
daemon.socketLocation	Location of the container manager control socket	/var/run
daemon.socketFile	Specify the socket file name in socketLocation (if you are not using containerd/docker/pouch/cri-o)
daemon.credentialProvider.enable	Whether to enable credential provider for image pull job	false
daemon.credentialProvider.hostPath	node dir of the credential provider plugin, kruise-daemon will mount the dir as a hostpath volume	credential-provider-plugin
daemon.credentialProvider.configmap	configmap name of the credential provider in kruise-system ns	credential-provider-config
daemon.credentialProvider.awsCredentialsDir	aws credentials dir if using AWS, for example: /root/.aws

other parameters

Parameter	Description	Default
enableKubeCacheMutationDetector	Whether to enable KUBE_CACHE_MUTATION_DETECTOR	false
webhookConfiguration.timeoutSeconds	The timeoutSeconds for all webhook configuration	30
serviceAccount.annotations	Annotations to patch for serviceAccounts	{}
externalCerts.annotations	Annotations to patch for webhook configuration and crd when featuregate EnableExternalCerts is enabled. For example, cert-manager.io/inject-ca-from: kruise-system/kruise-webhook-certs.	{}

Specify each parameter using the --set key=value[,key=value] argument to helm install or helm upgrade.

Optional: feature-gate

Feature-gate controls some influential features in Kruise:

Name	Description	Default	Effect (if closed)
PodWebhook	Whether to open a webhook for Pod create	true	SidecarSet/KruisePodReadinessGate disabled
KruiseDaemon	Whether to deploy kruise-daemon DaemonSet	true	ImagePulling/ContainerRecreateRequest disabled
DaemonWatchingPod	Should each kruise-daemon watch pods on the same node	true	For in-place update with same imageID or env from labels/annotations
CloneSetShortHash	Enables CloneSet controller only set revision hash name to pod label	false	CloneSet name can not be longer than 54 characters
KruisePodReadinessGate	Enables Kruise webhook to inject 'KruisePodReady' readiness-gate to all Pods during creation	false	The readiness-gate will only be injected to Pods created by Kruise workloads
PreDownloadImageForInPlaceUpdate	Enables CloneSet controller to create ImagePullJobs to pre-download images for in-place update	false	No image pre-download for in-place update
CloneSetPartitionRollback	Enables CloneSet controller to rollback Pods to currentRevision when number of updateRevision pods is bigger than (replicas - partition)	false	CloneSet will only update Pods to updateRevision
ResourcesDeletionProtection	Enables protection for resources deletion	true	No protection for resources deletion
TemplateNoDefaults	Whether to disable defaults injection for pod/pvc template in workloads	false	Should not close this feature if it has open
PodUnavailableBudgetDeleteGate	Enables PodUnavailableBudget for pod deletion, eviction	true	No protection for pod deletion, eviction
PodUnavailableBudgetUpdateGate	Enables PodUnavailableBudget for pod.Spec update	false	No protection for in-place update
WorkloadSpread	Enables WorkloadSpread to manage multi-domain and elastic deploy	true	WorkloadSpread disabled
InPlaceUpdateEnvFromMetadata	Enables Kruise to in-place update a container in Pod when its env from labels/annotations changed and pod is in-place updating	true	Only container image can be in-place update
StatefulSetAutoDeletePVC	Enables policies controlling deletion of PVCs created by a StatefulSet	true	No deletion of PVCs by StatefulSet
PreDownloadImageForDaemonSetUpdate	Enables DaemonSet controller to create ImagePullJobs to pre-download images for in-place update	false	No image pre-download for in-place update
PodProbeMarkerGate	Whether to turn on PodProbeMarker ability	true	PodProbeMarker disabled
SidecarSetPatchPodMetadataDefaultsAllowed	Allow SidecarSet patch any annotations to Pod Object	false	Annotations are not allowed to patch randomly and need to be configured via SidecarSet_PatchPodMetadata_WhiteList
SidecarTerminator	SidecarTerminator enables SidecarTerminator to stop sidecar containers when all main containers exited	false	SidecarTerminator disabled
CloneSetEventHandlerOptimization	CloneSetEventHandlerOptimization enable optimization for cloneset-controller to reduce the queuing frequency cased by pod update	false	optimization for cloneset-controller to reduce the queuing frequency cased by pod update disabled
ImagePullJobGate	Enables ImagePullJob to pre-download images	false	ImagePullJob disabled
ResourceDistributionGate	Enables ResourceDistribution to distribute configmaps or secret resources	false	ResourceDistribution disabled
DeletionProtectionForCRDCascadingGate	Enables DeletionProtection for crd cascading deletion	false	DeletionProtection for crd cascading deletion disabled

If you want to configure the feature-gate, just set the parameter when install or upgrade. Such as:

$ helm install kruise https://... --set featureGates="ResourcesDeletionProtection=true\,PreDownloadImageForInPlaceUpdate=true"

If you want to enable all feature-gates, set the parameter as featureGates=AllAlpha=true.

Optional: the local image for China

If you are in China and have problem to pull image from official DockerHub, you can use the registry hosted on Alibaba Cloud:

$ helm install kruise https://... --set  manager.image.repository=openkruise-registry.cn-shanghai.cr.aliyuncs.com/openkruise/kruise-manager

Best Practices

Installation parameters for K3s

Usually K3s has the different runtime path from the default /var/run. So you have to set daemon.socketLocation to the real runtime socket path on your K3s node (e.g. /run/k3s or /var/run/k3s/).

Installation parameters for AWS EKS

When using a custom CNI (such as Weave or Calico) on EKS, the webhook cannot be reached by default. This happens because the control plane cannot be configured to run on a custom CNI on EKS, so the CNIs differ between control plane and worker nodes.

To address this, the webhook can be run in the host network so it can be reached, by setting --set manager.hostNetwork=true when use helm install or upgrade.

Support webhook CA injection using external certification management tool

FEATURE STATE: Kruise v1.7.0

Kruise needs certificates to enable mutating, validating and conversion webhooks. By default, kruise will generate self-signed certificates for webhook server. If you want to use external certification management tool, e.g. cert-manager, you can follow these steps when install or upgrade:

1. Install external certification management tool, e.g. cert-manager.
2. Create issuer and certificate resources if you have not done this before.

apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
  name: kruise-webhook-certs
  # consistent with installation.namespace
  namespace: kruise-system
spec:
  # where to store the certificates
  # cert-manager would generate a secret kruise-system/kruise-webhook-certs with the certificates
  # DO NOT CHANGE THE SECRET NAME SINCE KRUISE READ CERTS FROM THIS SECRET
  secretName: kruise-webhook-certs
  dnsNames:
  - kruise-webhook-service.kruise-system.svc
  - localhost
  issuerRef:
    name: selfsigned-kruise
    kind: Issuer
---
apiVersion: cert-manager.io/v1
kind: Issuer
metadata:
  name: selfsigned-kruise
  namespace: kruise-system
spec:
  selfSigned: {}

3. During installation and upgrade, enable external certs support by setting featureGates=EnableExternalCerts=true and specify extra annotations that should be added to webhookconfiguration and CRD.

helm install kruise https://... --set featureGates="EnableExternalCerts=true" --set-json externalCerts.annotations='{"cert-manager.io/inject-ca-from":"kruise-system/kruise-webhook-certs"}'

Visit CA Injector - cert manager for more details.

Structured Logs

FEATURE STATE: Kruise v1.7.0

Logs are an essential aspect of observability and a critical tool for debugging. But OpenKruise logs have traditionally been unstructured strings, making any automated parsing difficult and any downstream processing, analysis, or querying challenging to do reliably.

From OpenKruise 1.7, we are adding support for structured logs, which natively support (key, value) pairs and object references. And logs can also be outputted in JSON format using helm install ... --set manager.loggingFormat=json.

For example, this invocation of InfoS:

klog.V(3).InfoS("SidecarSet updated status success", "sidecarSet", klog.KObj(sidecarSet), "matchedPods", status.MatchedPods,
"updatedPods", status.UpdatedPods, "readyPods", status.ReadyPods, "updateReadyPods", status.UpdatedReadyPods)

will result in this log:

I0821 14:22:35.587919       1 sidecarset_processor.go:280] "SidecarSet updated status success" sidecarSet="test-sidecarset" matchedPods=1 updatedPods=1 readyPods=1 updateReadyPods=1

Or, if helm install ... --set manager.loggingFormat=json, it will result in this output:

{
  "ts": 1724239224606.642,
  "caller": "sidecarset/sidecarset_processor.go:280",
  "msg": "SidecarSet updated status success",
  "v": 3,
  "sidecarSet": {
    "name": "test-sidecarset"
  },
  "matchedPods": 1,
  "updatedPods": 1,
  "readyPods": 0,
  "updateReadyPods": 0
}

Uninstall

Note that this will lead to all resources created by Kruise, including webhook configurations, services, namespace, CRDs, CR instances and Pods managed by Kruise controller, to be deleted!

Please do this ONLY when you fully understand the consequence.

To uninstall kruise if it is installed with helm charts:

$ helm uninstall kruise
release "kruise" uninstalled

Kruise State Metrics

kruise-state-metrics is a simple service that listens to the Kubernetes API server and generates metrics about the state of the objects. It is not focused on the health of the individual OpenKruise components, but rather on the health of the various objects inside, such as clonesets, advanced statefulsets and sidecarsets.

# Firstly add openkruise charts repository if you haven't do this.
$ helm repo add openkruise https://openkruise.github.io/charts/

# [Optional]
$ helm repo update

# Install the latest version.
$ helm install kruise openkruise/kruise-state-metrics --version 0.1.0